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Accounting Policies Segment Reporting and Accounts Receivable (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) segment customer	Dec. 31, 2017 USD ($) customer
Concentration Risk [Line Items]
Number of reportable segments | segment	2
Allowance for doubtful accounts | $	$ 0	$ 0
Accounts Receivable | Customer Concentration Risk
Concentration Risk [Line Items]
Number of customers | customer	2	1
Concentration risk, percentage	50.40%	22.00%

X

- Definition

Represent number of customers.

+ References

No definition available.

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X

- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
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-Name Accounting Standards Codification
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-Paragraph 1
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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